PREDICT: Omics-based models for prediction of hybrid performance in oilseed rape

杂种优势或杂种优势是改善异交作物产量表现的重要现象。在油菜(Brassica napus L.)中，杂交种如今占据了国际种子市场的主要份额。然而，与玉米等其他重要杂交作物相比，油菜的产量杂种优势水平相对较低。因此，油菜育种行业对更好地利用杂种优势来改善杂交性能非常感兴趣。本项目的目的是开发基于组学的油菜优良杂交种产量杂种优势预测模型。通过比较来自一大批优良亲本的DNA序列、代谢物和转录组数据，以及来自其F1后代的发育表型和田间产量评估的综合信息，将开发和测试预测杂交性能的模型。全基因组单核苷酸多态(SNP)基因分型将使用新的甘蓝型油菜60k SNP Infinium阵列实现，而转录分析、代谢分析和表型分析将分别利用最新的mRNA测序、质谱仪和高通量表型技术。根据以前的观察，基本的假设是发育和产量杂种优势受到共同的调节因素的影响，这些因素的特定等位基因组合，以及它们引起的代谢物和基因表达谱，与改善的杂种优势有关。我们的目标是确定一种“组学选择”图谱，以及相应的分析和统计方法，这些方法可以通过预先选择具有最高表现的新杂交组合潜力的亲本品系来共同用于简化育种过程。基因组、转录组或代谢预测因子的鉴定将进一步支持我们对油菜杂种优势表现的分子过程和机制的理解。通过与两家领先的德国杂交油菜生产商(Norddeutsche Pflanzucht Hans-Georg Lembke KG和Deutsche Saatveredelung AG)合作，我们将把基础和高价值植物育种过程的基础研究转移到一个具有强大商业潜力的杂交育种体系中。

Heterosis, or hybrid vigour, is an important phenomenon for improving the yield performance of outcrossing crops. In oilseed rape (Brassica napus L.), hybrids today make up the major share of the international seed market. However, in comparison to other important hybrid crops like maize, oilseed rape shows relatively low levels of yield heterosis. The oilseed rape breeding industry therefore has considerable interest in a more optimal utilisation of heterosis for improvement of hybrid performance. The aim of this project is to develop omics-based prediction models for seed yield heterosis in elite oilseed rape hybrids. Models for prediction of hybrid performance will be developed and tested by comparing DNA sequence, metabolite and transcriptome data from a large set of elite parental lines with comprehensive information from developmental phenotyping and field-based yield evaluations of their F1 offspring. Genome-wide single-nucleotide polymorphism (SNP) genotyping will be achieved using the new B. napus 60k SNP Infinium array, while the transcriptomic, metabolomic and phenomic analyses will take advantage of the latest mRNA sequencing, mass-spectrometry and high-throughput phenotyping technologies, respectively. The underlying hypothesis, derived from previous observations, is that developmental and yield heterosis are influenced by common regulatory factors and that specific allelic combinations of these factors, together with the metabolite and gene expression profiles they elicit, are associated with improved heterosis. We aim to identify an "omics selection" profile, along with corresponding analytical and statistical methods, that can together be used to streamline breeding processes by pre-selecting parental lines with highest potential for top performing new hybrid combinations. Identification of genomic, transcriptomic, or metabolomic predictors will furthermore support the advancement in our understanding of the molecular processes and mechanisms involved in heterosis manifestation in oilseed rape. By collaborating with two leading German producers of hybrid oilseed rape varieties (Norddeutsche Pflanzenzucht Hans-Georg Lembke KG and Deutsche Saatveredelung AG) we will transfer basic research on a fundamental and high-value plant breeding process into a system with a strong commercial potential for improvement of hybrid breeding.